Carburetor



Nov. 10, 1931. c, L, BA T AN 1,831,522

CARBURETOR Filed Oct. 5. 1929 fir 2/2 7 z to?? (m le; 545051101:

Patented Nov. 10, 1931 PATENT] OFFICE CHARLES L. BASTIA N', OF CHICAGO, ILLINOIS cannonnron Application filed October 8, 1929. Serial No. 397,023.

' vMy invention relates to improvements in carburetors for internal combustion eng nes. The principal object of my invention is to provide an improved carburetor structure n which a substantially constant vacuum 1s maintained in the carbureting chamber and the flow of fuel from the nozzle is var ed according to the volume of air passing through said chamber to produce a perfect combustible mixture of fuel and air throughout the entire range of speed of the engine. A further object is to mechanically connect the vacuum maintaining means and the fuel control means with the throttle to mainta n a definite operating relation between said mechanisms whereby the most eflicient mixture of fuel and air will be produced throughout the entire range of speed.

Other objects will appear hereinafter. Referring to the drawings Fig. 1 is a view in elevation of a carburetor structure embodying m invention, showing the means for operative y connectlng the several valves; Fig. 2 is a vertical section on the lme 2-2 of Fig. 1, the float chamber portion of the structure being shown partly 1n section;

Fig. 3 is a detail of the multiple et fuel nozzle; and

Fig. 4 is a detail of the valve member controlling said nozzle.

The structure shown in the drawings m which my invention is embodied, com rises a casing A at one side of which a suitable float chamber B is positioned. The structure is preferably mounted in vertical position in use, and the upper end of the casing is connected to the engine manifold by means of the flanges 1 in the usual manner. The casing has a cylindrical passage extending its entire length, with its lower end forming an intake open to the atmosphere and its upper end forming a mixture outlet communicating with the engine manifold. In the upper portion of this passage the throttle valve 2 is located for controlling the flow of mixture with the usual operating links (not shown) extending to the steering wheel of the automobile.

The lower or intake end portion of the passage in the casing is reduced in diameter sufficiently so that the throat 5 is substantially less, preferably about 30%, in cross-sectional area than the remaining passage above the throat. This reduced throat is controlled by an auxiliary or secondary throttle valve, preferably a butterfly, valve 6 similar to the main throttle valve 2. The main throttle 2 and secondary throttle 6 are spaced apart longitudinally of the passage to provide between thema carbureting chamber 7 in which the fuel nozzle 8 is positioned. By operating the main throttle valve and secondary throttle valve in proper relation to each other a substantially uniform pressure differential can be maintained between the carburetor chamber and the atmosphere, the. pressure within the carburetor chamber being sufiiciently less than the pressure beyond secondary valve 6 to produce in practice about 4 pounds vacuum. This constant can be maintained throughout the range of movement of the valves even though the volume of air flowing through'the carburetor passage varies in accordance with the requirements of the engine throughout its entire range of speed.

In order to maintain this definite operating relation of the main "and secondary throttle valves, the two valves are mechanlcally connected so that the operation of the main throttle valve is communicated to the secondar throttle whereby the secondary throttle is operated in unison therewith. A radial arm 10 is fastened to the projecting end of the shaft 3 of the mainthrottle valve, and a similar arm 11 is fastened to the shaft 7 of the auxiliary throttle valve. The two arms are connected by a link 12 so that the movement of the main throttle will be transmitted tothe auxiliary throttle. The link 11 is pivotally related to the radial arms to adapt its connection to the different angular positions assumed when the arms 10 and 11 rotate.

bolt 19. This provides a means by which the proper angular position. of the secondary butterfiy throttle with respect to the main throttle may be adjusted.

The degree to which the main throttle valve is opened to control the speedof the engine will be thus translated, through the medium of the radial arms and link connection, into the proper degree of opening of the secondary throttle valve to maintain a con-- stant vacuum in the carbureting chamber throughout the entire range of engine speed. The relative degree of movement of the throttles ,can be accordingly determined by adjusting the sleeves l and 16 on the arms and 11 to regulate the operating length 1 cues-e radial arms.

The volume or quantity of air passing through the carburetor chamber varies, of course, in accordance with the demands of the engine. When the throttle valves practically close the passage there is just a sullic'ient quantity or" air flowing through the to form a mixture with the fuel for idling speed of the engine. "When the throttles open wide the passage through the carburetor the maximum volume of air for fuel mixture corresponding to maximum engine speed flows through the carburetor. The degree of vacuum within the carbureting chamber, however, will remain practically constant regardless of the variation in volfuel in proportion to ume of air flowing therethrough.

B maintaining a. constant vacuum in the mixing chamber I am enabled to supply fuel in the proper proportion. to any volume or air flowing through the chamber to produce a completely combustible mixture. I accomplish this fuel regulation by providing a multi le jet nozzle in the carbureting chamber, which is adapted to increase the supply of the increase of volume of air accordance with the demands of the engine, with the result that a perfect mixture is produced throughout the entire range of engine demand. la the structure shown in the drawings this nozzle comprises the sleeve member 8 which extends transversely of the carburetor chamber substantially midway between the two throttle valves. One end of the sleeve is set in a recess in the inner wall of the carburetor chamber and a packing washer is provided to make other end of the sleeve extends throu h a threaded boss 21 on the outer wall 0 the casing A and is held in position by a packing gland threaded on said boss, thus pmtight joint. The

viding a tight joint at this end. The sleeve has a plurality of jet openings or orifices 23 disposed in a straight longitudinal line, and

point upwardly toward the main throttle valve. These jet orifices vary progressively in size with the smallest at one end of the row and the largest at the other end of the row.

The control of these jet orifices is accom-' plished by the rotary valve stem 24 which is rotatably mounted within the sleeve 8. This stem has a hollow-passage 25 which communicates with the source of fuel supply. The valve stem has a plurality of openings 26 corresponding in size and relative position with the jet orifices 23 except that-they are progressively positioned angularly' around the valve stem so that they can be registered one at a time with the corresponding jet orifices 23 by the rotation of the stem. However, a longitudinal slot 27 is cut in the outer surface of the valve stem in line with each opening 26 to insure full openings register ing with the orifices. By rotating the valve stem to progressively register the valve openings with the jet orifices the flow of fuel can be accurately regulated in proportion to the volume of air flowin g through the carburetor chamber. The rotation of the valve stem is accomplished by mechanically connecting it with the shaft of the main throttle valve. The end of the valve stem projects beyond the end of the sleeve and has a segmental gear 29 fastened thereto which meshes with and is driven by a similar gear 30 fastened on the shaft '23 e: the main throttle valve, whereby as the main throttle valve is operated corresponding rotation will be imparted to the valve stem 24. The valve 24 is'so related to the throttle valve that as the throttle valves increase the flow of air through the carburetor chamber the valve 24 will correspondingly increase the flow of fuel through the nozzle orifices. The parts are so proportioned that the increasing flow of fuel will be in the proper relation-to the increasing volume of air to produce a properly combustible mix-- ture.

The usual float chamber B is provided at the side of the casing for maintaining a proper level of fuel with respect to the fuel nozzle. In this structure the chamber is formed integrally with the carburetor casing A, and a fuel passage 81 is provided which commu nicates at its lower end with the float chamber and its upper end with the open end of the nozzle sleeve 8.

I am aware that changes may be made in construction, operation and arrangement of parts withoutdeparting from the spirit of the invention and I hereby reserve the right to make all such changes as fairly fall within the scope of the appended claims.

I claim:

1. In a carburetor, the combination of a casing embodying an air inlet and. a mixture see l ll

said fuel inlet, and said mixing chamber,

means for moving said valve member, butterfly valves in said inlet and said outlet, and means for simultaneously moving said butterfly valves and the moving means for said valve member to maintain a predetermined relation between the butterfly valves and said valves and the valve member whereby a predetermined quantity of air may ass through said mixing chamber to be mixed with a predetermined quantity of fuel emitted through an opening in said sleeve proportioned to the quantity of air passing through the mixing chamber.

2. In a carburetor, a casing having a tubular mixture outlet at one endthereof and a tubular airinlet at the other end thereof with a mixing chamber between said outlet and said inlet, a sleeve extended across said mixing chamber and having openings therein of successively greater diameter, means providing a fuel inlet, a valve member in said sleeve having a passage therein connected with the fuel inlet and having discharge openings therein successively and separately registerable with the openings in said sleeve to establish communication between said fuelinlet and the mixing-chamber, means for moving said valve member, a butterfly valve in said outlet and movable therein to control passage therethrough, a butterfly valve in said inlet and movable therein to control passage therethrough, means for simultaneously and uniformly moving said butterfly valves, and means for simultaneously moving said valve member whereby communication will be established between said fuel inlet and said mixing chamber through an opening in said sleeve of a magnitude directly proportioned to the quantityof air passing through said mixing chamber. 0 i

3. In a carburetor, a casing having an unrestricted passage therein embodying a mixture outlet and an air inlet of smaller size than said outlet and having a mixing cham ber between said outletand said inlet, a sleeve extended diametrically across said mixing chamber, means providing, a iuel inlet, a valve member in said sleeve having a passage therein connected with said fuel inlet and having discharge openings therein successively and separately registerable with the openings in said sleeve to establish communication tween said fuel inlet and said mixing chamber, means for preventing leakage about said valve member,"-means ,for movin said valve member, abutterfly' valve in sai outlet and movable-thereinto control passage therethrough, a "butterfly-valve in said inlet and movable therein to control-passage there through, meansfor simultaneously and-uniformly moving said butterfly-valves whereby apredeterminedquantity of'air may pass throughsaid mixing chamber and a difference' in pressure may be maintainedbetween said outlet and said inlet, and meansformd tivating the moving meansfor said valve member whereby communication'may be es tablished betweensaid iu'el inletand said mixing chamber throughan opening in said sleeve of a magnitude in direct proportion to the quantity of air passing therethrough. 4. In a carburetor, a casin havingan un-' restricted passag'etherein em odying a mixture outlet and an air inlet of smaller size than said outlet and'having a mixing chamber betweensaid outlet and said inlet, asleeve extended diametrically across saidmixing chamber, means providing a fuel inlet, a

valve member in said'sleeve having a passage therein connected with said fuel inlet and having discharge openings therein successively and separately 'registerable with the openings in said sleeve to establish communication betweensaid fuel inlet and said mixing chamber, meansforpreventing leakageabout said valve member, a gear connected to saidvalve member, a butterfly valve in said outlet and movable therein to control passage therethrough, a butterfly valve in said inlet and movable therein to control passage therethrough, threaded arms extended diametrically from supporting shaft for said butterfly valves, sleeves movable therealong, nuts for retaining said sleeves in determined positions on said arms, a link pivotally connected to said sleeves whereby said arms and said but terfiy valves may be simultaneously and uniiormly moved, a gear connected on the supporting shaft for said outlet valve and meshed with said gear connected to said valve member whereby said valve member may be moved simultaneously with the movement of said butterfly valves to establish communica-' tions of said butterfly valves and the difierence in size of said outlet and said inlet.

5. In a carburetor, a casing having an unrestricted passage therein embodying a mix-- ture outlet and an air inlet of smaller size than said outlet andhaving a mixing chamber betweensaid outlet and said inlet,"a shaft extended diametrically across said outlet,

means for journaling said shaft, a butterfly valve carried by said shaft in said outlet to control passage-therethrough, a shaft extended diametrically across said inlet, means for journaling said shaft, a butterfly valve carried by said shaft for controlling assage through said inlet, a threaded arm xed to the first-named shaft, a threaded arm fixed to the second-named shaft, sleeves on said arms, nuts for retaining said sleeves in adjusted positions on said arms, a link having the ends thereof pivotally connected to said sleeves whereby said arms, shafts, and valve members carried thereby may be simultaneously and uniformly moved, a sleeve extended diametrically across said mixing chamber having a plurality of openings therein of successively greater diameter, means providing a fuel inlet, a valve member in said sleeve having a passage therein communicating with said fuel inlet and having discharge openings therein successively and registerable with the openin s in said sleeve to establish communication between said fuel inlet and said mixing chamber, means for preventing leakage past said valve member, a gear on said firstnamed shaft, and a gear fixed to said valve member and meshing with the first-named gear whereby said valve member may be moved simultaneously with the movement of said butterfly valves to establish communication between said fuel inlet and said mixing chameo her through an opening in said sleeve of a magnitude directly proportioned to the quantity of air passing through said mixing chamber that is regulated by the positions of said butterfly valves and the difference in size between said outlet and said inlet.

CHARLES L. BASTIAN. 

